KR20210055402A - Supported hybrid metallocene catalyst, and method for preparing homo polyethylene using the same - Google Patents

Abstract

The present invention relates to a hybrid supported catalyst which maintains excellent catalytic activity over time and enables the production of homopolyethylene having uniform physical properties and structures, and a manufacturing method of homopolyethylene using the same. The hybrid supported catalyst includes a carrier; an alkylaluminoxane-based first cocatalyst supported on the carrier; a second trialkylaluminum-based cocatalyst having an alkyl group with 8 or more carbon atoms supported on the first cocatalyst; and different first and second metallocene compounds supported on the second cocatalyst.

Description

Hybrid supported catalyst and method for producing homopolyethylene using the same {SUPPORTED HYBRID METALLOCENE CATALYST, AND METHOD FOR PREPARING HOMO POLYETHYLENE USING THE SAME}

The present invention relates to a hybrid supported catalyst that maintains excellent catalytic activity over time and enables the production of homopolyethylene having uniform physical properties and structure, and a method for producing homopolyethylene using the same.

Since the Ziegler-Natta catalyst widely applied to the existing commercial process is a multi-active point catalyst, it is characterized by a wide molecular weight distribution of the resulting polymer, and the composition distribution of the comonomer is not uniform, so there is a limit to securing desired physical properties.

On the other hand, metallocene catalysts have a narrow molecular weight distribution of polymers produced by single active point catalysts with one type of active point, and greatly increase molecular weight, stereoregularity, crystallinity, and especially the reactivity of comonomers depending on the structure of the catalyst and ligand. It has the advantage of being adjustable.

The metallocene catalyst system is composed of a combination of a main catalyst composed of a transition metal compound mainly composed of a group 4 metal and a cocatalyst composed of an organometallic compound composed mainly of a group 13 metal such as aluminum. Polymers such as polyolefins having a narrow molecular weight distribution may be prepared according to the characteristics of the single active point of the catalyst.

On the other hand, in recent years, in order to obtain a polyolefin that satisfies various physical properties such as a relatively wide molecular weight distribution and excellent processability, but a large molecular weight and excellent mechanical properties, two or more metallocene catalysts are co-supported. Catalysts are widely used.

However, in such a hybrid supported catalyst, all of the activities of metallocene catalysts supported by multiple types are high, and the polymerization properties of these catalysts must be simultaneously expressed.Therefore, various studies to uniformly improve the catalytic activity or degree of expression at the same time. Is going on. For example, it has been reported that when an alkyl aluminum-based cocatalyst or a scavenger is used, the polymerization activity of the hybrid supported catalyst can be improved.

However, in the case of a hybrid supported catalyst using additives such as the cocatalyst or scavenger, the catalyst is deformed over the time of storage and use, thereby reducing polymerization activity, or preventing the polymerization characteristics of each catalyst from being uniformly expressed. There was a downside to becoming. As a result, depending on the use of the hybrid supported catalyst, there has been a problem in that the molecular structure of the polyolefin prepared using the same, for example, homopolyethylene, is deformed or the physical properties are not maintained, making it impossible to prepare a resin with uniform physical properties. .

For this reason, despite the passage of time, development of a hybrid supported catalyst that maintains excellent catalytic activity and enables the production of a resin having a uniform physical property and structure has been continuously requested.

Accordingly, the present invention provides a hybrid supported catalyst that maintains excellent catalytic activity despite the passage of time and enables the production of homopolyethylene having uniform physical properties and structure.

The present invention also provides a method for producing homopolyethylene capable of producing homopolyethylene having uniform physical properties and structure in high yield by using the hybrid supported catalyst.

The present invention is a carrier; An alkylaluminoxane-based first cocatalyst supported on the carrier; A trialkyl aluminum-based second cocatalyst having an alkyl group having 8 or more carbon atoms supported on the first cocatalyst; And it provides a hybrid supported catalyst comprising different first and second metallocene compounds supported on the second cocatalyst.

The present invention also provides a method for producing a homopolyethylene comprising the step of polymerizing ethylene in the presence of the hybrid supported catalyst according to the present invention.

The hybrid supported catalyst of the present invention can maintain excellent catalytic activity despite the lapse of storage and use time of the catalyst by controlling the use and support sequence of a specific cocatalyst. In addition, since the formation of catalyst inactive species due to the interaction of the cocatalyst and the metallocene compound can be suppressed, the expression ratio of each metallocene compound can be uniformly maintained. And it becomes possible to prepare a homopolyethylene that maintains the molecular structure.

Therefore, by using the hybrid supported catalyst, it is possible to produce homopolyethylene having uniform physical properties and structure in high yield.

Hereinafter, a hybrid supported catalyst and a method for preparing the same according to a specific embodiment of the present invention, and a method for preparing polyethylene using the hybrid supported catalyst will be described.

According to an embodiment of the invention, a carrier; An alkylaluminoxane-based first cocatalyst supported on the carrier; A trialkyl aluminum-based second cocatalyst having an alkyl group having 8 or more carbon atoms supported on the first cocatalyst; And a hybrid supported catalyst including different first and second metallocene compounds supported on the second cocatalyst.

In the hybrid supported catalyst of one embodiment, an alkylaluminoxane-based first cocatalyst and a trialkylaluminum-based second cocatalyst are sequentially supported on a carrier, and the first and second metallocene compounds as active species on the second cocatalyst Is supported. According to the structure of the hybrid supported catalyst of this embodiment, the second trialkylaluminum-based cocatalyst that improves the activity of the metallocene compound may act together with the first and second metallocene compounds to exhibit excellent polymerization activity. .

In addition, in such a hybrid supported catalyst, a long chain alkyl group having 8 or more carbon atoms having a long chain length is bonded to the second trialkylaluminum-based cocatalyst. It is believed that such a long-chain alkyl group may cause a steric hindrance effect in the catalyst structure, thereby inhibiting the mutual reaction between the second cocatalyst and the first and second metallocene compounds, and thus the formation of inactive catalytic species. In addition, due to the steric hindrance effect of the long-chain alkyl group, β-elimination of the aluminum complex may also be suppressed, and the formation of the catalyst inactive species may be further suppressed.

Therefore, in the hybrid supported catalyst of one embodiment, it is possible to suppress the formation of an inactive species that decreases the overall interaction of the metallocene compound and the second cocatalyst and the activity or expression of the catalyst, and the use of the hybrid supported catalyst Alternatively, even if the storage time elapses, the polymerization activity of the hybrid supported catalyst and the expression ratio of each catalyst may be uniformly and excellently maintained.

As a result, when the hybrid supported catalyst of the above embodiment is used, it becomes possible to manufacture homopolyethylene that maintains uniform physical properties and molecular structure, and the excellent polymerization activity of the catalyst is maintained, resulting in high homopolyethylene having uniform physical properties and structure. It becomes possible to manufacture in yield.

On the contrary, when a trialkyl aluminum having a short-chain alkyl group such as triethyl aluminum or triisobutyl aluminum is used as the second cocatalyst, the catalyst inertness that interferes with polyethylene polymerization by reacting with the metallocene compounds. It will form a large number of species. Accordingly, it was confirmed that the physical properties and product structure of the resin were changed, such as the activity of the catalyst decreased with the passage of time, the expression ratio of each catalyst, etc. changed, and the molecular weight of the resin changed.

Hereinafter, a hybrid supported catalyst and a method for preparing the same according to an embodiment will be described in more detail.

In the hybrid supported catalyst of the above embodiment, the carrier is a structure for supporting each cocatalyst and metallocene compounds, and may be any carrier known to support a metallocene catalyst or the like.

Such carriers may contain hydroxyl groups on the surface. The less the amount of hydroxy groups (-OH) on the surface of the support is possible, the better, but it is practically difficult to remove all hydroxy groups. Therefore, the amount of the hydroxy group can be adjusted by the method and conditions for preparing the carrier or drying conditions (temperature, time, drying method, etc.). For example, the amount of hydroxy groups on the surface of the carrier is preferably 0.1 to 10 mmol/g, and more preferably 0.5 to 1 mmol/g. If the amount of the hydroxy group is less than 0.1 mmol/g, the reaction site with the cocatalyst decreases, and if it exceeds 10 mmol/g, it is not preferable because it may be due to moisture other than the hydroxy group present on the surface of the carrier. not.

At this time, in order to reduce side reactions due to some remaining hydroxy groups after drying, a carrier having a high reactive siloxane group participating in the support may be preserved while chemically removing this hydroxy group may be used.

In this case, it is preferable that the carrier has a highly reactive hydroxyl group and a siloxane group together on the surface. Examples of such a carrier include silica dried at high temperature, silica-alumina, or silica-magnesia, and these are usually oxides such _{as Na 2} O, K ₂ CO ₃ , BaSO ₄ , or Mg(NO ₃ ) ₂ , Carbonate, sulfate or nitrate components.

The carrier is preferably used in a sufficiently dried state before the cocatalyst or the like is supported. At this time, the drying temperature of the carrier is preferably 200 to 800°C, more preferably 300 to 600°C, and most preferably 400 to 600°C. When the drying temperature of the carrier is less than 200°C, there is too much moisture so that the moisture on the surface and the cocatalyst react, and when it exceeds 800°C, the pores on the surface of the carrier are combined and the surface area decreases, and there are many hydroxyl groups on the surface. It is not preferable because it disappears and only siloxane groups remain, and the reaction site with the cocatalyst decreases.

Meanwhile, in the hybrid supported catalyst of one embodiment, the first alkylaluminoxane-based cocatalyst is primarily supported on the carrier. The first cocatalyst may be a linear, circular, or network-like alkylalunoxane-based compound having a repeating unit bonded thereto, and specific examples thereof include methylaluminoxane (MAO), ethylaluminoxane, isobutylaluminoxane, or butyl And aluminoxane. Among these, in view of the overall activity of the hybrid supported catalyst, and the like, methylaluminoxane may be preferably used.

In addition, the first cocatalyst may be supported in a ratio of 0.01 to 3 mmol, or 0.1 to 2 mmol, or 0.2 to 1.5 mmol with respect to 1 g of the carrier.

If the supporting ratio of the first cocatalyst is too low, the degree of formation of active species of the catalyst is reduced, so that the overall polymerization activity of the hybrid supported catalyst may be reduced. Conversely, when the supporting ratio of the first cocatalyst is too high, an excessive amount of cocatalyst An additional process and cost may be required for removing the catalyst, and it is difficult to expect additional activity improvement of the catalyst.

In the hybrid supported catalyst of one embodiment, a second trialkylaluminum-based cocatalyst having an alkyl group having 8 or more carbon atoms or an alkyl group having 8 to 10 carbon atoms is supported on the first cocatalyst. As already described above, as the second trialkylaluminum-based cocatalyst having a long-chain alkyl group is supported between the first cocatalyst and the metallocene compound, the polymerization activity of the hybrid supported catalyst is excellent despite the passage of time. It may be maintained, and the structure and physical properties of a polyolefin prepared using a hybrid supported catalyst, for example, homopolyethylene, may be uniformly maintained.

Specific examples of such a second cocatalyst include a trialkyl aluminum-based compound having at least one long-chain alkyl group, more specifically trioctyl aluminum, tridecyl aluminum, or tridodecyl aluminum, among which catalytic activity and In consideration of the uniform physical properties and structure of polyethylene, trioctyl aluminum can be preferably used.

In addition, the second cocatalyst may be supported in a ratio of 0.05 to 2 mmol, or 0.1 to 1.5 mmol, or 0.2 to 1 mmol with respect to 1 g of the carrier.

When the supporting ratio of the second cocatalyst is too low, the activity of the catalyst may be lowered. On the contrary, when the supporting ratio of the second cocatalyst is too high, the formation of catalyst inactive species increases and the polymerization activity decreases over time. Or, the physical properties and/or structure of the resin may be changed.

Meanwhile, in the hybrid supported catalyst of the above-described exemplary embodiment, the first metallocene compound may include a compound represented by Formula 1 below, and the second metallocene compound may include a compound represented by Formula 2 below.

[Formula 1]

In Formula 1,

M ₁ is a Group 4 transition metal;

Cp ₁ is any one cyclic compound selected from the group consisting of cyclopentadienyl, indenyl, 4,5,6,7-tetrahydro-1-indenyl and fluorenyl, and at least one hydrogen of the cyclic compound is Each independently substituted with one of C1 to 20 alkyl, C1 to C20 alkoxy, C2 to C20 alkoxyalkyl, C6 to C20 aryl, C7 to C20 alkylaryl, or C7 to C20 arylalkyl. Can;

Z ₁ And Z ₂ is the same as or different from each other, and each independently halogen, C1 to C20 alkyl, C2 to C10 alkenyl, C6 to C20 aryl, C7 to C20 alkylaryl, or C7 to C20 arylalkyl;

B is carbon, silicon, or germanium;

R ₁ to R ₃ are the same as or different from each other, and each independently hydrogen, C1 to C20 alkyl, C2 to C20 alkenyl, C1 to C20 alkoxy, C2 to C20 alkoxyalkyl, C6 to C20 aryl, C7 To C20 alkylaryl, or C7 to C20 arylalkyl;

[Formula 2]

In Chemical Formula 2,

M ₂ is a Group 4 transition metal;

Cp ₂ and Cp ₃ are the same as or different from each other, and each independently selected from the group consisting of cyclopentadienyl, indenyl, 4,5,6,7-tetrahydro-1-indenyl and fluorenyl Is a cyclic compound, and at least one hydrogen of the cyclic compound is each independently C1 to 20 alkyl, C1 to C20 alkoxy, C2 to C20 alkoxyalkyl, C6 to C20 aryl, C7 to C20 alkylaryl, or C7 to May be substituted with any one of C20 arylalkyl;

Z ₃ And Z ₄ are the same as or different from each other, and each independently halogen, C1 to C20 alkyl, C2 to C10 alkenyl, C6 to C20 aryl, C7 to C20 alkylaryl, or C7 to C20 arylalkyl.

In the structure of each of these metallocene compounds, the substituents of each formula may be defined as follows.

The halogen may be fluorine (F), chlorine (Cl), bromine (Br), or iodine (I).

C1 to C20 alkyl may be straight chain, branched chain or cyclic alkyl. Specifically, the C1 to C20 alkyl is a straight-chain alkyl having 1 to 20 carbon atoms; Straight-chain alkyl having 1 to 10 carbon atoms; Straight-chain alkyl having 1 to 5 carbon atoms; Branched or cyclic alkyl having 3 to 20 carbon atoms; Branched or cyclic alkyl having 3 to 15 carbon atoms; Or it may be a branched chain or cyclic alkyl having 3 to 10 carbon atoms. More specifically, alkyl having 1 to 20 carbon atoms is a methyl group, ethyl group, n-propyl group, iso-propyl group, n-butyl group, iso-butyl group, tert-butyl group, n-pentyl group, iso-pentyl group, or It may be a cyclohexyl group and the like.

C2 to C20 alkenyl may be straight chain, branched chain or cyclic alkenyl. Specifically, the C2 to C20 alkenyl is a straight chain alkenyl having 2 to 20 carbon atoms, a straight chain alkenyl having 2 to 10 carbon atoms, a straight chain alkenyl having 2 to 5 carbon atoms, a branched chain alkenyl having 3 to 20 carbon atoms, and 3 carbon atoms. To 15 branched alkenyl, branched chain alkenyl having 3 to 10 carbon atoms, cyclic alkenyl having 5 to 20 carbon atoms, or cyclic alkenyl having 5 to 10 carbon atoms. More specifically, the alkenyl having 2 to 20 carbon atoms may be ethenyl, propenyl, butenyl, pentenyl or cyclohexenyl.

C1 to C20 alkoxy may be a linear, branched or cyclic alkoxy group. Specifically, the C1 to C20 alkoxy is a straight chain alkoxy group having 1 to 20 carbon atoms; Straight chain alkoxy having 1 to 10 carbon atoms; A straight chain alkoxy group having 1 to 5 carbon atoms; Branched or cyclic alkoxy having 3 to 20 carbon atoms; Branched or cyclic alkoxy having 3 to 15 carbon atoms; Or it may be a branched chain or cyclic alkoxy having 3 to 10 carbon atoms. More specifically, the alkoxy having 1 to 20 carbon atoms is a methoxy group, ethoxy group, n-propoxy group, iso-propoxy group, n-butoxy group, iso-butoxy group, tert-butoxy group, n-pentoxy group, iso -It may be a pentoxy group, a neo-pentoxy group, or a cyclohectoxy group.

C2 to C20 alkoxyalkyl has a structure including -Ra-O-Rb, and may be a substituent in which one or more hydrogens of alkyl (-Ra) are substituted with alkoxy (-O-Rb). Specifically, the C2 to C20 alkoxyalkyl is a methoxymethyl group, methoxyethyl group, ethoxymethyl group, iso-propoxymethyl group, iso-propoxyethyl group, iso-propoxyhexel group, tert-butoxymethyl group, tert It may be a -butoxyethyl group or a tert-butoxyhexyl group.

C6 to C20 aryl may mean monocyclic, bicyclic or tricyclic aromatic hydrocarbons. Specifically, the C6 to C20 aryl may be a phenyl group, a naphthyl group, or an anthracenyl group.

C7 to C20 alkylaryl may mean a substituent in which at least one hydrogen of the aryl is substituted by alkyl. Specifically, the C7 to C20 alkylaryl may be methylphenyl, ethylphenyl, n-propylphenyl, iso-propylphenyl, n-butylphenyl, iso-butylphenyl, tert-butylphenyl or cyclohexylphenyl.

C7 to C0 arylalkyl may mean a substituent in which one or more hydrogens of alkyl are substituted by aryl. Specifically, the C7 to C0 arylalkyl may be a benzyl group, phenylpropyl, or phenylhexyl.

Examples of the Group 4 transition metal include titanium, zirconium, and hafnium.

In addition, the first metallocene compound represented by Formula 1 may be, for example, a compound represented by the following structural formula, but the present invention is not limited thereto.

In addition, the second metallocene compound represented by Formula 2 may be, for example, a compound represented by one of the following structural formulas, but is not limited thereto.

The first and second metallocene compounds described above may be each independently supported in a ratio of 0.02 to 1 mmol based on 1 g of the carrier in consideration of their polymerization activity and expression ratio.

The loading order of the above-described first and second metallocene compounds is not particularly limited when they are supported on the second cocatalyst after the above-described second cocatalyst is already supported. However, in consideration of the expression ratio of each of these metallocene compounds, these metallocene compounds may be sequentially supported on the second cocatalyst, in order of the first metallocene compound and the second metallocene compound. have.

The hybrid supported catalyst of one embodiment described above may be prepared according to the loading and production conditions of a conventional hybrid supported catalyst, except for the loading order of each component described above. For example, the preparation of such a hybrid supported catalyst can be carried out by appropriately using high temperature support and low temperature support, and specifically, when the first cocatalyst and the second cocatalyst are supported on the carrier, the temperature condition may be performed at 25 to 100°C. I can. In this case, the loading time of the first cocatalyst and the second cocatalyst can be determined by a person skilled in the art in consideration of the loading ratio of each cocatalyst.

In addition, in sequentially supporting the first and second cocatalysts and the first and second metallocene compounds, a solvent may be used for contact reaction between each component and a carrier, and the reaction may be performed without a solvent. . Solvents that can be used include aliphatic hydrocarbon solvents such as hexane or pentane, aromatic hydrocarbon solvents such as toluene or benzene, hydrocarbon solvents substituted with chlorine atoms such as dichloromethane, ether solvents such as diethyl ether or THF, acetone, Most organic solvents, such as ethyl acetate, are mentioned, and hexane, heptane, toluene, or dichloromethane is preferable.

In addition, the reaction temperature between the first and second metallocene compounds and the carrier may be -30°C to 150°C, preferably room temperature to 100°C, and more preferably 30 to 80°C. The reacted supported catalyst may be used as it is by filtration of the reaction solvent or distillation under reduced pressure, and if necessary, it may be used after filtering with an aromatic hydrocarbon such as toluene.

On the other hand, the above-described hybrid supported catalyst may itself be used for polymerization of olefin-based monomers such as ethylene. In addition, the hybrid supported catalyst may be prepared and used as a prepolymerized catalyst by contact reaction with ethylene or the like in advance.

When the above-described hybrid supported catalyst is used, for example, in the process of polymerizing ethylene to produce homopolyethylene, high polymerization activity may be exhibited, and the physical properties of polyethylene may be maintained while maintaining the high polymerization activity despite the passage of time. And the structure can be maintained.

Accordingly, according to another embodiment of the present invention, there is provided a method for producing a homopolyethylene comprising the step of polymerizing ethylene in the presence of the hybrid supported catalyst of the embodiment described above.

The polymerization reaction may be carried out while supplying ethylene as a monomer using one continuous slurry polymerization reactor, a loop slurry reactor, a gas phase reactor, or a solution reactor.

The hybrid supported metallocene catalyst is an aliphatic hydrocarbon solvent having 5 to 12 carbon atoms, such as pentane, hexane, heptane, nonane, decane, and isomers thereof, and aromatic hydrocarbon solvents such as toluene and benzene, dichloromethane, chlorobenzene, and It can be dissolved or diluted in a hydrocarbon solvent substituted with the same chlorine atom and injected. The solvent used here is preferably treated with a small amount of alkyl aluminum to remove a small amount of water or air acting as a catalyst poison. It is also possible to further use a cocatalyst.

The homopolyethylene obtained according to the above manufacturing method has a weight average molecular weight (Mw) of about 100,000 to about 400,000 g/mol or about 150,000 to about 300,000 g/mol and a molecular weight distribution of 2 to 4, or 2.5 to 3.5 (MWD) can be expressed, and despite the lapse of the use time of the catalyst, such physical properties and the molecular structure of the homopolyethylene can be uniformly maintained to be prepared.

Hereinafter, the present invention will be described in detail through examples of the present invention. However, embodiments of the present invention may be modified in various forms, and the scope of the present invention should not be construed as being limited by the embodiments described below.

< Example >

Manufacturing example One: No. 1 Metallocene Preparation of the compound Example

(tBu-O-(CH ₂ ) ₆ )(CH ₃ )Si (C ₅ (CH ₃ ) ₄ )( tBu -N) TiCl ₂ of Produce

After 50 g of Mg(s) was added to a 10 L reactor at room temperature, 300 mL of THF was added. After about 0.5 g of I ₂ was added, the temperature of the reactor was maintained at 50°C. After the reactor temperature was stabilized, 250 g of 6-t-butoxyhexyl chloride was added to the reactor at a rate of 5 mL/min using a feeding pump. As 6-t-butoxyhexyl chloride was added, the reactor temperature was observed to increase by about 4 to 5°C. The mixture was stirred for 12 hours while continuously adding 6-t-butoxyhexyl chloride. After 12 hours of reaction, a black reaction solution was obtained. After taking 2 mL of the resulting black solution, water was added to obtain an organic layer, and 6-t-butoxyhexane was confirmed through 1H-NMR. It was found that the Grignard reaction proceeded well from the 6-t-butoxyhexane. Thus, 6-t-butoxyhexyl magnesium chloride was synthesized.

After adding _{500 g of MeSiCl 3} and 1 L of THF to the reactor, the temperature of the reactor was cooled to -20°C. 560 g of the synthesized 6-t-butoxyhexyl magnesium chloride was added to the reactor at a rate of 5 mL/min using a feeding pump. After the completion of feeding of the Grignard reagent, the reactor was stirred for 12 hours while slowly raising the temperature to room temperature. It was confirmed that a _{white MgCl 2} salt was formed after 12 hours of reaction. 4 L of hexane was added to remove the salt through labdori to obtain a filter solution. After the obtained filter solution was added to the reactor, hexane was removed at 70°C to obtain a pale yellow liquid. The obtained liquid was confirmed to be the desired methyl(6-t-butoxy hexyl)dichlorosilane {Methyl(6-t-butoxy hexyl)dichlorosilane} compound through 1H-NMR.

1H-NMR (CDCl3): 3.3 (t, 2H), 1.5 (m, 3H), 1.3 (m, 5H), 1.2 (s, 9H), 1.1 (m, 2H), 0.7 (s, 3H)

After adding 1.2 mol (150 g) of tetramethylcyclopentadiene and 2.4 L of THF to the reactor, the temperature of the reactor was cooled to -20°C. It was added to the reactor at a rate of 5 mL/min using an n-BuLi 480 mL feeding pump. After adding n-BuLi, the reactor was stirred for 12 hours while slowly raising the temperature to room temperature. After 12 hours of reaction, an equivalent amount of methyl (6-t-butoxy hexyl) dichlorosilane (326 g, 350 mL) was rapidly added to the reactor. After stirring for 12 hours while slowly raising the reactor temperature to room temperature, the reactor temperature was cooled to 0° C., and 2 equivalents of t-BuNH ₂ were added. The reactor was stirred for 12 hours while slowly raising the temperature to room temperature. After 12 hours of reaction, THF was removed, and 4 L of hexane was added to obtain a filter solution from which salts were removed through Labdori. After the filter solution was added to the reactor again, hexane was removed at 70° C. to obtain a yellow solution. The obtained yellow solution was confirmed to be a methyl (6-t-butoxyhexyl) (tetramethyl CpH) t-butylaminosilane (Methyl(6-t-buthoxyhexyl) (tetramethylCpH) t-Butylaminosilane) compound through 1H-NMR. .

_{TiCl 3} (THF) ₃ (10 mmol) in the dilithium salt of the ligand at -78°C synthesized in THF solution from n-BuLi and the ligand dimethyl(tetramethylCpH)t-butylaminesilane (Dimethyl(tetramethylCpH)t-Butylaminosilane) ) Was added rapidly. The reaction solution was stirred for 12 hours while slowly raising from -78°C to room temperature. After stirring for 12 hours, an equivalent amount of PbCl ₂ (10 mmol) was added to the reaction solution at room temperature, followed by stirring for 12 hours. After stirring for 12 hours, a dark black solution having a blue color was obtained. After removing THF from the resulting reaction solution, hexane was added to filter the product. After removing hexane from the filter solution to be obtained, the desired ([methyl(6-t-buthoxyhexyl)silyl(η5-tetramethylCp)(t-Butylamido)]TiCl ₂ ) is (tBu-O-(CH ₂ ) _{6 from 1H-NMR.} )(CH ₃ )Si(C ₅ (CH ₃ ) ₄ )(tBu-N)TiCl ₂ .

1H-NMR (CDCl ₃ ): 3.3 (s, 4H), 2.2 (s, 6H), 2.1 (s, 6H), 1.8 ~ 0.8 (m), 1.4 (s, 9H), 1.2 (s, 9H), 0.7 (s, 3H)

Manufacturing example 2: Second Metallocene Preparation of the compound Example

[ tBu -O-(CH ₂ ) ₆ - C ₅ H ₄ ] ₂ ZrCl ₂ of Produce

_{Using 6-chlorohexanol, t-Butyl-O-(CH 2} ) ₆ -Cl was prepared by the method suggested in the literature (Tetrahedron Lett. 2951 (1988)), and NaCp was reacted thereto. t-Butyl-O-(CH ₂ ) ₆ -C ₅ H ₅ was obtained (yield 60%, bp 80°C / 0.1 mmHg).

In addition, t-Butyl-O-(CH ₂ ) ₆ -C ₅ H ₅ was dissolved in THF at -78°C, and normal butyllithium (n-BuLi) was slowly added, the temperature was raised to room temperature, and then reacted for 8 hours. . The previously synthesized lithium salt solution was slowly added to the suspension solution of _{ZrCl 4} (THF) ₂ (1.70 g, 4.50 mmol)/THF (30 mL) at -78°C again at room temperature. It was further reacted for 6 hours at.

All volatile substances were vacuum-dried, and a hexane solvent was added to the obtained oily liquid substance to filter it out. After vacuum drying the filtered solution, hexane was added to induce a precipitate at low temperature (-20°C). Filter the obtained precipitate at low temperature to form a white solid [tBu-O-(CH ₂ ) ₆ -C ₅ H ₄ ] ₂ ZrCl ₂ A compound was obtained (yield 92%).

¹ H NMR (300 MHz, CDCl ₃ ): 6.28 (t, J = 2.6 Hz, 2 H), 6.19 (t, J = 2.6 Hz, 2 H), 3.31 (t, 6.6 Hz, 2 H), 2.62 ( t, J = 8 Hz), 1.7-1.3 (m, 8H), 1.17 (s, 9H).

¹³ C NMR (CDCl ₃ ): 135.09, 116.66, 112.28, 72.42, 61.52, 30.66, 30.61, 30.14, 29.18, 27.58, 26.00.

<Preparation of hybrid supported catalyst Example >

Comparative example One

1-1 Carrier dry

Silica (SYLOPOL 948 manufactured by Grace Davison) was dehydrated at 600° C. for 12 hours under vacuum.

1-2 Preparation of supported catalyst

49.7 mL of a 10 wt% methylaluminoxane (MAO)/toluene solution was added to a glass reactor, and 9.1 g of silica prepared at a temperature of 40° C. was added, followed by stirring at 200 rpm for 16 hours while raising the reactor temperature to 60° C. After lowering the temperature to 40° C. again, 465 mmg (0.1 mmol/g SiO ₂ ) of the first metallocene compound (K2 catalyst) of Preparation Example 1 was dissolved in toluene to make a solution, and then added to the reactor and stirred for 1 hour. Made it. _{Thereafter, 550mmg (0.1 mmol/g SiO 2} ) of the second metallocene compound (K1 catalyst) of Preparation Example 2 was dissolved in toluene to form a solution, and after being added to the reactor, the mixture was stirred for 2 hours.

After the reaction was completed, the stirring was stopped, the catalyst was settled, the toluene layer was separated and removed, and the pressure was reduced at 40°C to remove the remaining toluene to prepare a hybrid supported catalyst.

Comparative example 2

1-1 Carrier dry

Silica (SYLOPOL 948 manufactured by Grace Davison) was dehydrated at 600° C. for 12 hours under vacuum.

1-2 Preparation of supported catalyst

49.7 mL of a 10 wt% methylaluminoxane (MAO)/toluene solution was added to a glass reactor, and 9.1 g of silica prepared at a temperature of 40° C. was added, followed by stirring at 200 rpm for 16 hours while raising the reactor temperature to 60° C.

Then, after lowering the temperature to 40° C. again _{, 2.7 mL of a 1M hexane solution of 0.3 mmol/g SiO 2} of triethylaluminum was added, followed by stirring again for 1 hour.

_{Next, 465mmg (0.1 mmol/g SiO 2} ) of the first metallocene compound (K2 catalyst) of Preparation Example 1 was dissolved in toluene to form a solution, and after being added to the reactor, the mixture was stirred for 1 hour. _{Thereafter, 550mmg (0.1 mmol/g SiO 2} ) of the second metallocene compound (K1 catalyst) of Preparation Example 2 was dissolved in toluene to form a solution, and after being added to the reactor, the mixture was stirred for 2 hours.

After the reaction was completed, the stirring was stopped, the catalyst was settled, the toluene layer was separated and removed, and the pressure was reduced at 40°C to remove the remaining toluene to prepare a hybrid supported catalyst.

Comparative example 3

1-1 Carrier dry

Silica (SYLOPOL 948 manufactured by Grace Davison) was dehydrated at 600° C. for 12 hours under vacuum.

1-2 Preparation of supported catalyst

49.7 mL of a 10 wt% methylaluminoxane (MAO)/toluene solution was added to a glass reactor, and 9.1 g of silica prepared at a temperature of 40° C. was added, followed by stirring at 200 rpm for 16 hours while raising the reactor temperature to 60° C.

Subsequently, after lowering the temperature to 40° C. again _{, 2.7 mL of a 1M hexane solution of 0.3 mmol/g SiO 2} of triisobutylaluminum was added, followed by stirring again for 1 hour.

_{Next, 465mmg (0.1 mmol/g SiO 2} ) of the first metallocene compound (K2 catalyst) of Preparation Example 1 was dissolved in toluene to form a solution, and after being added to the reactor, the mixture was stirred for 1 hour. _{Thereafter, 550mmg (0.1 mmol/g SiO 2} ) of the second metallocene compound (K1 catalyst) of Preparation Example 2 was dissolved in toluene to form a solution, and after being added to the reactor, the mixture was stirred for 2 hours.

After the reaction was completed, the stirring was stopped, the catalyst was settled, the toluene layer was separated and removed, and the pressure was reduced at 40°C to remove the remaining toluene to prepare a hybrid supported catalyst.

Example One

1-1 Carrier dry

Silica (SYLOPOL 948 manufactured by Grace Davison) was dehydrated at 600° C. for 12 hours under vacuum.

1-2 Preparation of supported catalyst

49.7 mL of a 10 wt% methylaluminoxane (MAO)/toluene solution was added to a glass reactor, and 9.1 g of silica prepared at a temperature of 40° C. was added, followed by stirring at 200 rpm for 16 hours while raising the reactor temperature to 60° C.

Subsequently, after lowering the temperature to 40° C. again _{, 2.7 mL of a 1M hexane solution of 0.3 mmol/g SiO 2} of trioctyl aluminum was added, followed by stirring again for 1 hour.

_{Next, 465mmg (0.1 mmol/g SiO 2} ) of the first metallocene compound (K2 catalyst) of Preparation Example 1 was dissolved in toluene to form a solution, and after being added to the reactor, the mixture was stirred for 1 hour. _{Thereafter, 550mmg (0.1 mmol/g SiO 2} ) of the second metallocene compound (K1 catalyst) of Preparation Example 2 was dissolved in toluene to form a solution, and after being added to the reactor, the mixture was stirred for 2 hours.

After the reaction was completed, the stirring was stopped, the catalyst was settled, the toluene layer was separated and removed, and the pressure was reduced at 40°C to remove the remaining toluene to prepare a hybrid supported catalyst.

Example 2

49.7 mL of a 10 wt% methylaluminoxane (MAO)/toluene solution was added to a glass reactor, and 9.1 g of silica prepared at a temperature of 40° C. was added, followed by stirring at 200 rpm for 16 hours while raising the reactor temperature to 60° C.

Subsequently, after lowering the temperature to 40° C. again _{, 2.7 mL of a 1M hexane solution of 0.3 mmol/g SiO 2} of trioctyl aluminum was added, followed by stirring again for 1 hour.

_{Next, 698mmg (0.15 mmol/g SiO 2} ) of the first metallocene compound (K2 catalyst) of Preparation Example 1 was dissolved in toluene to make a solution, and the mixture was added to the reactor and stirred for 1 hour. _{Thereafter, 550mmg (0.1 mmol/g SiO 2} ) of the second metallocene compound (K1 catalyst) of Preparation Example 2 was dissolved in toluene to form a solution, and after being added to the reactor, the mixture was stirred for 2 hours.

After the reaction was completed, the stirring was stopped, the catalyst was settled, the toluene layer was separated and removed, and the pressure was reduced at 40°C to remove the remaining toluene to prepare a hybrid supported catalyst.

< Experimental example >

Ethylene homopolymerization

After adding 400 mL of hexane to an isolated system filled with argon using a PARR reactor, 1 g of trimethylaluminum was added to dry the inside of the reactor, and the hexane was discarded. After adding 400 mL of hexane again, 0.2 g of triethylaluminum was added, and a mixed supported catalyst improved by 7 mg was put into the reactor in a glove box filled with argon. Polymerization was carried out at 80° C. for 1 hour.

In addition, after allowing the hybrid supported catalysts of Comparative Examples 1 and 3 and Examples 1 and 2 to stand for 1 month, ethylene homopolymerization was performed under the same conditions as above to be a subject for comparison.

The polymerization activity for each of the catalysts prepared above, and the molecular weight and molecular weight distribution of the obtained polymer are shown in Table 1 below.

division Polymerization activity
(kg-PE/g-Cat.) Weight average molecular weight
(g/mol) Molecular weight distribution
(MWD) Comparative Example 1
(Carrier + MAO + K2/K1) 13.0 216000 3.2 Comparative Example 1 (after 1 month) 13.0 220000 3.1 Comparative Example 2 (Carrier + MAO + TEAL + K2/K1) 7.6 243000 3.3 Comparative Example 3 (Carrier + MAO + TIBAL + K2/K1) 16.0 232000 3.3 Comparative Example 3 (after 1 month) 6.3 275000 3.0 Example 1 (carrier + MAO + TOA + K2/K1) 15.7 223000 3.2 Example 1 (after 1 month) 15.0 226000 3.2 Example 2 (carrier + MAO + TOA + K2/K1) 14.0 253000 3.4 Example 2 (after 1 month) 13.6 251000 3.4

Referring to Table 1, it was confirmed that when the hybrid supported catalyst of Example was used, excellent polymerization activity was exhibited, and excellent polymerization activity was maintained even after 1 month, while no change in physical properties of homopolyethylene was observed.

In contrast, in the case of Comparative Examples 1 and 2, it was confirmed that the polymerization activity was low compared to the Example.

In addition, in Comparative Example 3, after leaving the catalyst for 1 month, it was confirmed that not only the polymerization activity decreased, but also the molecular weight of homopolyethylene was greatly changed, resulting in a substantial change in physical properties.

Claims (12)

carrier;
An alkylaluminoxane-based first cocatalyst supported on the carrier;
A trialkyl aluminum-based second cocatalyst having an alkyl group having 8 or more carbon atoms supported on the first cocatalyst; And
Hybrid supported catalyst comprising different first and second metallocene compounds supported on the second cocatalyst.
The hybrid supported catalyst of claim 1, wherein the first metallocene compound is represented by Formula 1:
[Formula 1]

In Formula 1,
M ₁ is a Group 4 transition metal;
Cp ₁ is any one cyclic compound selected from the group consisting of cyclopentadienyl, indenyl, 4,5,6,7-tetrahydro-1-indenyl and fluorenyl, and at least one hydrogen of the cyclic compound is Each independently substituted with one of C1 to 20 alkyl, C1 to C20 alkoxy, C2 to C20 alkoxyalkyl, C6 to C20 aryl, C7 to C20 alkylaryl, or C7 to C20 arylalkyl. Can;
Z ₁ And Z ₂ is the same as or different from each other, and each independently halogen, C1 to C20 alkyl, C2 to C10 alkenyl, C6 to C20 aryl, C7 to C20 alkylaryl, or C7 to C20 arylalkyl;
B is carbon, silicon, or germanium;
R ₁ to R ₃ are the same as or different from each other, and each independently hydrogen, C1 to C20 alkyl, C2 to C20 alkenyl, C1 to C20 alkoxy, C2 to C20 alkoxyalkyl, C6 to C20 aryl, C7 To C20 alkylaryl, or C7 to C20 arylalkyl.
The hybrid supported catalyst according to claim 2, wherein the compound of Formula 1 is one of the following structural formulas:

The hybrid supported catalyst of claim 1, wherein the second metallocene compound is represented by Formula 2:
[Formula 2]

In Chemical Formula 2,
M ₂ is a Group 4 transition metal;
Cp ₂ and Cp ₃ are the same as or different from each other, and each independently selected from the group consisting of cyclopentadienyl, indenyl, 4,5,6,7-tetrahydro-1-indenyl and fluorenyl Is a cyclic compound, and at least one hydrogen of the cyclic compound is each independently C1 to 20 alkyl, C1 to C20 alkoxy, C2 to C20 alkoxyalkyl, C6 to C20 aryl, C7 to C20 alkylaryl, or C7 to May be substituted with any one of C20 arylalkyl;
Z ₃ And Z ₄ are the same as or different from each other, and each independently halogen, C1 to C20 alkyl, C2 to C10 alkenyl, C6 to C20 aryl, C7 to C20 alkylaryl, or C7 to C20 arylalkyl.
The hybrid supported catalyst according to claim 4, wherein the compound of Formula 2 is one of the following structural formulas:

The hybrid supported catalyst according to claim 1, wherein the first cocatalyst is methylaluminoxane, and the second cocatalyst is trioctyl aluminum, tridecyl aluminum, or tridodecyl aluminum.
The hybrid supported catalyst according to claim 1, wherein the first cocatalyst is supported in a ratio of 0.01 to 3 mmol with respect to 1 g of the support.
The hybrid supported catalyst according to claim 1, wherein the second cocatalyst is supported in a ratio of 0.05 to 2 mmol with respect to 1 g of the support.
The hybrid supported catalyst according to claim 1, wherein the supported ratios of the first metallocene compound and the second metallocene compound are the same or different from each other, and are each independently supported in a ratio of 0.02 to 1 mmol with respect to 1 g of the carrier. .
The hybrid supported catalyst according to claim 1, wherein silica, alumina, magnesia, or a mixture thereof is used as the support.
The hybrid supported catalyst according to claim 1, wherein the first metallocene compound and the second metallocene compound are sequentially supported.
A method for producing a homopolyethylene comprising the step of polymerizing ethylene in the presence of the hybrid supported catalyst of any one of claims 1 to 11.